What Does Foamy Vaginal Discharge Mean? Causes & What to Do

Key takeaways:

• Any vaginal discharge that mixes with air or results from an infection can become foamy.
• Trichomoniasis, an STI, or bacterial vaginosis are also common causes of foamy discharge.
• The color of a foamy vaginal discharge can range from clear to dark, with milky white, yellow, or green being the most common.

In most cases, foamy vaginal discharge is a sign of infection. A common cause of foamy vaginal discharge is the sexually transmitted infection (STI) trichomoniasis, sometimes referred to as “trich.” Another common culprit, bacterial vaginosis (BV), is a change in your normal bacteria balance, which may or may not result from sex.

STIs spread through sexual intercourse. This means that even after treatment, you could be at risk of contracting the infection again, especially if you got it from a partner. Mutual, simultaneous treatment for your partner, even when your partner has no symptoms, is recommended.

Is it normal to have foamy vaginal discharge?

The short answer is no. Although natural phenomena could explain a foamy vaginal discharge, it’s unlikely. For example, theoretically, the act of intercourse can introduce air into the vagina, which can cause a foamy consistency. If this is the case, there should be no discoloration or unpleasant odor.

The more likely explanation, though, is an infection. Sexually-transmitted infections (STIs) are the most common cause of foamy vaginal discharge. While learning you may have been exposed to an STI can be upsetting, it’s not in the best interest of you or any sexual partners to avoid treatment. If you suspect an STI, seek medical care right away and know that there is no need to feel shame or embarrassment.

What is foamy vaginal discharge?

A foamy vaginal discharge generally indicates a change in your vaginal health. You may also describe it as “frothy” or “bubbly.” It usually arises due to an infection, the presence of other substances, or by mixing with air or another gas.

Typically, foamy discharge will have other characteristics that point to an infection. These can include symptoms like pain, burning, itching, or an unusual odor.

Common causes of foamy vaginal discharge

The normal vaginal secretions help lubricate and hydrate the delicate tissues. Also present are mucous secretions from microscopic glands in the cervix. When an abnormal process acts on this natural moisture, its consistency will change. The following are some causes of a foamy vaginal discharge, from most common to least:

Trichomoniasis

Trichomonas vaginalis is the parasite that causes trichomoniasis, a common STI. It is not dangerous, although it increases the risk of preterm labor and premature birth in pregnancy. Even if you are not pregnant, this is still an infection that requires treatment. Not everyone will show signs of infection, so both you and your partner need to be tested, even if only one of you is experiencing symptoms.

Bacterial vaginosis

Your vagina has a natural population of helpful bacteria, the lactobacilli. These help balance the vaginal pH level—an important factor in maintaining healthy function.

No one knows what causes bacterial vaginosis (BV). This is because it occurs as both an STI and other non-infectious reasons. BV occurs when other bacteria replace the normal, healthy population of lactobacilli. This can cause the vagina to become less acidic. It often comes with a yellow discharge, which can seem foamy. Like trichomoniasis, it can have a “fishy” odor from the bacteria.

Other bacterial infection

Other types of bacterial infections might also cause a foamy discharge. Gonorrhea and chlamydia, both STIs, can cause foamy discharge that ranges from yellow to green. Likewise, Escherichia coli (E. coli), a bacterium that normally resides in the rectum, can sometimes migrate to the vagina and cause an infection. This can happen during sexual intercourse or result from poor hygiene practices.

Yeast infection

A yeast infection typically causes a thick, white discharge that may appear chunky or “foamy” in some cases. It also causes itching and burning but does not usually involve an unpleasant odor.

Menopause

Menopause usually causes clear, watery discharge due to the breakdown of vaginal cells. As such, it can also become foamy with infection.

What foamy vaginal discharge can mean based on your menstrual cycle

The phases of your menstrual cycle don't influence infections of the vagina. Infection happens regardless, and no part of your cycle gives you any special protection.

However, it is important to point out that bacterial infections will thrive on the old blood and tissue debris of your period. In that case, blood will be mixed with a vaginal discharge, discoloring it (from pink to black and any hue of red and brown in between).

What foamy discharge may mean based on appearance, texture, or another symptom or condition

A foamy discharge should make you suspect either trichomoniasis or BV, but any discharge can become foamy. Also, mixed infections (more than one infection present at the same time) can change the appearance of any discharge.

The characteristics below have a considerable overlap of causes. For each, we list only the most likely cause:

• White, foamy vaginal discharge: A mixed infection of yeast with bacteria or trichomoniasis.
• Green, foamy vaginal discharge: Trichomoniasis, BV, a bacterial infection alone, or a mixed infection involving any of these.
• Foamy vaginal discharge with an unpleasant odor: Same as above. This can also be the result of a foreign body in the vagina (e.g., a forgotten tampon or condom)—a prime breeding ground for bacteria.
• Foamy vaginal discharge during pregnancy: Trichomoniasis, BV, a bacterial infection alone, or a mixed infection. A beta-hemolytic streptococcus infection is a serious concern in this case, as it can spread to the newborn during labor.
• Foamy vaginal discharge after menstruation: Same as above, but there may be some discoloration due to the blood and cellular shedding involved in menstruation.
• Foamy vaginal discharge after sexual intercourse: Same as above. Additionally, the physical action of intercourse may dislodge fluids in the vagina. Foamy discharge after intercourse could also be due to the presence of semen.

Read our guides on vaginal discharge colors and vaginal discharge odors for more.

When you should see a doctor about foamy vaginal discharge

If you experience foamy discharge, you should suspect an infection until proven otherwise. As such, it's always a good idea to seek proper evaluation by a medical professional.

You should see a doctor for:

• Any foamy vaginal discharge, particularly if it’s discolored or has a foul, strong or “fishy” odor.
• Any foamy vaginal discharge accompanied by burning or itching.

You should go to the emergency room if:

You have a foamy vaginal discharge accompanied by:

• Fever
• Severe cramping
• Pelvic, abdominal, or back pain
• Painful urination or bowel movements
• Nausea or vomiting
• Abdominal distension

Questions to ask your doctor about foamy vaginal discharge

• What’s the process for proper diagnosis and treatment of foamy discharge?
• How will I know if the treatment is successful?
• Should I inform my partner of my diagnosis?
• If I’m pregnant, does my diagnosis pose any risks to me or my pregnancy?

How to get rid of or treat foamy vaginal discharge

Since foamy vaginal discharge usually indicates an infection, you will likely need medication. Your doctor may prescribe multiple medications if the infection is mixed.

Antibiotics

Antibiotics can help treat trichomoniasis, BV, and a number of other bacterial infections like gonorrhea and chlamydia.

Probiotics

Cultures of lactobacillus can be inserted vaginally with a suppository. For BV, however, antibiotics are the preferred treatment.

Antifungal

Even with a bacterial infection diagnosis, you may be prescribed an antifungal medication to address a mixed yeast infection. The pill form has the advantage of clearing yeast from your rectum, preventing recurrent yeast infections.

Frequently asked questions: foamy vaginal discharge

If you have a vagina, foamy discharge is probably not the norm, so it may raise the following questions when it occurs:

Is foamy vaginal discharge unhealthy?

Yes, it’s safe to assume vaginal discharge is unhealthy because it’s almost always a sign of an infection. While treatable, vaginal infections can still be dangerous, so it’s important to seek medical attention for foamy discharge.

Is it normal to have foamy discharge for weeks or months?

It is not normal to have a foamy discharge, much less for weeks or months. Nobody should let any foamy vaginal discharge go ignored for any length of time. It might not be an emergency, but it is definitely something that requires medical attention.

Final thoughts on foamy discharge

A foamy vaginal discharge is almost always a sign of an infection. Therefore, it’s important not to ignore it or assume that it’s normal or will resolve on its own. Trichomoniasis is the most common cause of foamy discharge, but bacterial vaginosis and other infections could also be to blame. A medical evaluation of both you and your partner(s), if applicable, may be necessary to identify the cause of your discharge and treat it effectively.

General Medicine follows a strict editorial process, including using real experts to write our articles, vetted primary sources, fact-checking, a secondary medical review, and updates as necessary. This article was medically reviewed and fact checked by Dr. Pallabi Sanyal-Dey, MD.

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